Jules, I have obtained wad cutters in odd sizes from Henry Krank's. By finding the size nearest but tighter and they have polished them out to the correct size for me for a modest fee. I needed an 18 bore cutter for a muzzle loader and had a 20 bore cutter they opened up slightly. I do know someone with a Daw that was successfully nitro proofed. I have one but marked Frederick Gates of Derby but I will stick to black in mine. Worth a ring to Kranks. Lagopus....